Tap-tempo metronome and beat looper
The Tap-Tempo Metronome is a tap-controlled or tap-tempo metronome and beat looper.
You tap the piezo speaker to set the rhythm. The display shows the beats per minute, and the two buttons adjust the speed.
You can tap patterns into it, up to 12 beats long. As long as you tap the pattern in three times, it jumps in and continues beeping in that rhythm. If you hold one of the buttons while turning the metronome on, the pitch of the beep will be higher or lower, so you can play with more than one at a time.
More details are available on the Tap-Tempo Metronome project page.
The kit contains a Tap-Tempo Metronome printed circuit board, a 3xAAA battery holder, a preprogrammed PIC16F685 microcontroller, a .3″ 20 pin DIP socket, three 0.3″ seven segment LED displays, two push buttons, one power switch, three NPN transistors, one .10 uF ceramic capacitor, one piezo speaker, one power protection diode, and a 10 kΩ resistor.
The contents are also listed and explained individually on the Parts List portion of the Tap-Tempo Metronome project page.
The Tap-Tempo Metronome is a through-hole kit. It requires basic soldering skill. At a minimum, you'll need a soldering iron, solder, and a diagonal cutters. It requires 3 AAA batteries, which are not included. Clear instructions are available at the Tap-Tempo Metronome project webpage.
It usually takes less than an hour to build, but it may take more or less time depending upon your experience with soldering.
This kit is open source hardware. We make the hardware source files like the schematic and the pcb files available for anyone to use as long as they credit us and release any modifications as open source hardware. The schematic and pcb files are available on the Tap-Tempo Metronome download page.
When you're finished building the kit, let us know how it went! We use feedback to improve future versions of our kits, and the warm fuzzies help us make more kits! Let us know in the forum or via email.